1. Summary of the Invention
The present inventions relate generally to pressurized respiratory therapy and, more particularly, to face mask supports for providing pressurized gas to the airways of a user.
2. Description of the Related Art
Airway patency may be related to a number of sleep related disorders, including snoring and sleep apnea for example. As a person ages, airway patency may be reduced due to loss of muscle tone in the muscles of the throat which normally serve to prevent the tissues from impinging on the airway. This condition may be more severe in patients who are obese, have naturally narrow airways or airways that may be partially blocked by tonsils, soft palate or uvula. One result can be snoring as the tissues vibrate as air may be forced through the narrowed airway under heightened pressure. Snoring may be disruptive to sleep; for the snorer not only keeps companions awake but will himself awaken many times in the night. This sleep disturbance can lead to feelings of tiredness or exhaustion during the day and a decrease in mental and physical performance.
In certain situations, the condition can be lethal. When narrowing of the airway proceeds to complete occlusion, the condition is commonly termed sleep apnea. A faulty feedback loop between the brain and the respiratory system lets the airway completely collapse until the brain registers low oxygen levels, high carbon dioxide levels or labored breathing, and the user awakens to resume breathing. These constant jump starts, which can happen as often as once a minute or more, cause an erratic heart rate and fluctuating blood pressure. In susceptible patients, this condition can lead to cardiovascular death.
Continuous positive airway pressure (CPAP), as well as other positive airway pressure therapies, may be used to alleviate the symptoms of snoring or sleep apnea by delivering air or gas under a pressure sufficient to mimic the effect of the natural waking tone of the throat muscles in holding the soft tissues around the airway from partially or totally occluding the airway passage.
Patients, other than those with airway problems, can also benefit from positive airway pressure therapies. This include patients with weakened respiratory muscles who cannot pull air into their lungs, such as those with post polio or amyotrophic lateral sclerosis disease, patients with traumatic nerve damage or adult respiratory distress.
Positive airway pressure apparatus are generally comprised of a blower for providing a stream of air or gas under pressure, a mask, and tubing to connect the mask to the blower source. The mask can cover both the mouth and nose, the nose alone, have plugs that insert only into the nares, or a mouthpiece in the mouth. Whatever the configuration, the mask must have, as a minimum, a means of sealing the mask to the face so that the blower gas does not escape, thereby reducing the pressure to the airway. Vents must be provided for exhaled gases. Preferably the vents are placed so as to avoid the eyes of the user. A mask support may be necessary to hold the mask and tubing in proper apposition.
User compliance with positive airway pressure therapies is sometimes a problem. Many of the masks currently available are uncomfortable, tend to be dislodged during sleep or disconnected from the blower source. Prior face mask systems have included straps that extended across the face of a user to provide a tension to a mask to assist in sealing the mask. Such straps frequently cause user discomfort and can contribute to a user's in compliance with the recommended therapy.
If the mask is a full face mask covering both nose and mouth or a nasal mask covering only the nose, the peripheries of the mask will touch the bridge of the nose, the upper or lower lip and must seal around the malar region. Individual variations in the topography, especially of the malar region, make it necessary to hold the mask to the face with some pressure. It has been shown that a double seal, with a semi-rigid internal support and a flexible skirt can be inflated with air, forming a seal that more readily conforms to the malar region. The ideal mask support may be usable with any variety of full face, nasal, or oral masks to accommodate individual needs and preferences.
Accordingly, a need exists for a mask support that may be comfortable, does not apply pressure to small or sensitive areas of the head and may be not easily dislodged or disconnected from its blower source.